Dimout curtain fabrics partially inhibit the passage of light, although not 100%, like blackout fabrics. The dimming is achieved by adding a black weft during the weaving process. The level of dimming of a dimout curtain fabric will depend on the colour of the fabric, the orientation of the window and the intensity of the outside light. A dark-coloured dimout curtain fabric has a higher blackout level than a light-coloured dimout curtain fabric.
A dimout curtain fabric will be more effective in north-facing rooms compared to other configurations. Similarly, a dimout curtain fabric will block light better at the end of a winter day - twilight - than on a south-facing summer day at noon.
For total blackout - especially in light colours - choose blackout curtain fabrics.
These are fabrics with a blackout rating of level 1 or 2 according to the EN14501 standard.
Fabrics that block light out at an illumination level greater than 10 lux are considered to be level 1. At over 1,000 lux, they are considered as level 2.